There is one disc my 6SE (2010) won't play sometimes, a reload or two and it plays. It's over 78 minutes long, may be a problem reading it, though it's actually disc 2 of a 2cd set and the other one is fine. I have had no trouble at all with any other CDs, although it is sensitive to scratches and greasy fingerprints (which occasionally find their way onto CDs...quick wipe and it's fine).
I can play one disc on repeat for days on end (for burn in), but not one track programmed in memory on repeat - it has stopped playing, and also scrambled the display or meant the track number doesn't change from 1 to 2 when playing a different disc. Since I don't need to play one track repeatedly, it doesn't really matter, but it is a fault.
I've informed Cyrus of all of this, they are helpful but said I'd need to send the player back with the discs to see if they can replicate thefault. For one disc (out of 100s) and a problem that only occurs by doing something I never do in normal listening, I didn't think it was worth it. Will be reminding them of it if I upgrade to 8SE in the future though...